Very interested in question #1. Getting wired ExpertWiFi EBG15 this week. EBA63 does what you want, so I imagine the EBM68 and EBR63 will work in AP mode that way as well. I may be purchasing EBR63 to act as AImesh nodes.
Dual Band WiFi 6 PoE Access Point, seamless roaming, support up to 5 SSIDs and VLAN, 100+ devices, easy management app, powered by PoE or AC adapter
www.asus.com
3 year warranty should mean 3 years of support. I do remember reading that asus is committed to the "expertwifi" line with new hardware already planned.